Spacers are interposed between a pair of electrodes disposed in a liquid crystal cell of liquid crystal display and a liquid crystal substance is sealed in a space surrounded with the electrodes and spacers to thereby form a liquid crystal layer. When the thickness of this liquid crystal layer is not uniform, the image displayed on the liquid crystal cell becomes mottled and causes lighting-time contrast degradation. Therefore, the uniformity of the thickness of liquid layer inside the liquid crystal cell is desirable. Further, the uniformity of the thickness of the liquid crystal layer inside the liquid crystal cell is also required, when the displayed image is changed over at a high speed or when an image of large viewing angle is displayed.
Still further, for realizing a large-scope display free from mottles on the currently employed large-scope liquid crystal display device of STN mode, it is required in greater degree to uniformalize the thickness of the liquid crystal layer inside the liquid crystal cell.
It is common practice to interpose, in sparsely dispersed form, spherical particles of uniform size between electrodes of the liquid crystal cell, namely to employ spherical particles as interelectrode spacers of the liquid crystal cell, for uniformalizing the thickness of the liquid crystal layer inside the liquid crystal cell. Particles of an organic resin such as polystyrene and fine particles of silica are used as such spherical particles.
However, the use of organic resin particles such as polystyrene particles as the interelectrode spacers of the liquid crystal cell invites the problem that the organic resin particles are too soft to maintain the uniformity of the thickness of the liquid crystal layer inside the liquid crystal cell. For example, if nonuniform pressure is applied to the liquid crystal layer inside the liquid crystal cell, the spacers are deformed in accordance with the nonuniformity of the pressure to thereby disenable maintaining the uniformity of the thickness of the liquid crystal layer inside the liquid crystal cell.
On the other hand, when fine particles of silica are used as the interelectrode spacers of the liquid crystal cell, unsharpness of particle-size distribution of silica fine particles invites the problem that the thickness of the liquid crystal layer inside the liquid crystal cell is rendered nonuniform because of the smallness of the compressive deformation of the silica fine particles. Furthermore, when the liquid crystal display is exposed to low temperatures with void formation, namely low-temperature bubbling, another problem occurs between the liquid crystal layer and the electrode of the liquid crystal cell, because the thermal expansion coefficient of the liquid crystal layer is different from that of the spacers.
Consequently, for solving the above problems, various proposals have been made which comprise using fine particles having appropriate elasticity and mechanical recovery as the spacers.
For example, it has been proposed to employ fine particles composed mainly of an organic resin such as a vinyl plastic or a hybrid of inorganic material and organic material (see Japanese Patent Laid-open Publication No. 4(1992)-313727 and Japanese Patent Laid-open Publication No. 5(1993)-80343) and to employ fine particles of a hydrolyzate of an organosilicon compound such as tetraethoxysilane (see Japanese Patent Laid-open Publication No. 6(1994)-250193 and Japanese Patent Laid-open Publication No. 7(1995)-80343).
However, these fine particles are unsatisfactory as the interelectrode spacers of the liquid crystal cell because, when nonuniform load is applied to the liquid crystal layer, the particles are deformed in accordance with the nonuniformity of the load to thereby disenable maintaining the uniformity of the thickness of the liquid crystal layer.